import hashlib
import os.path

def get_md5(path):
    if not os.path.exists(path):
        return None
    
    myhash=hashlib.md5()
    file=open(path,'rb')
    while True:
        data=file.read(4096)
        if not data:
            break
        myhash.update(data)
    file.close()
    return myhash.hexdigest()

#notice file path here
print(get_md5("test.mp4"))
